How to read resistor color codes

Resistors are printed with different colors, so maybe you're wondering what all these colors represent? This article will answer your questions, so let's get started!

How to Read a Resistor

• What are resistor color codes?
• History of Resistor Color Coding
• Resistor Color Chart
• How to Read Resistor Color Codes
• Common resistor color code questions

What are resistor color codes?

Let's start with a brief definition of resistor color codes. Resistor color codes are the use of different colors to indicate resistance values, multipliers, tolerances, and temperature coefficients, and then each color corresponds to a specific numerical value.
These color codes allow you to quickly identify the values and perform simple calculations to arrive at the resistance value without having to measure or consult additional markings.

History of Resistor Color Coding

In the early days, manufacturers marked resistors in their own way. in the 1920's, the Radio Manufacturers Association (RMA) developed the RMA Resistor Color Code and adopted it as the fixed resistor color code marking.
With the passage of time, the latest standard in existence is the revised IEC 60062:2016/AMD1:2019, published by the International Electrotechnical Commission (IEC) in 2019.

Resistor Color Chart

Below is a table of the values corresponding to the colors, and to remember it better, remember this: Bad Beer Rots Out Your Guts But Vodka Goes Well - Get Some Now.

How to Read Resistor Color Codes

There are four types of resistor color bands: 3 band, 4 band, 5 band and 6 band. The number of color bands depends on the precision of the resistor needed, here are the steps to read the resistor color code.

1. First of all, you need to distinguish the head and the tail. Many resistors will have the color bands concentrated at one end, which is the head, and the gold and silver tolerance values are usually at the tail.

2. Hold the tail of the resistor with your right hand, and look at the color ring from left to right, corresponding to the color shown above, determine the value and record it.

3. There are different formulas for different ring numbers, which are explained in detail below:

3 band resistor

The default tolerance value of 3 band resistor is ±20%, which is usually used by amateurs who do not require high resistance value. The first two color bands for the first two digits of the resistance value, the third color ring indicates the multiplier, against the above resistor color table were: brown for 1, black for 0, gold for the multiplier x 0.1. Calculated: 10x0.1 = 1Ω.

4 band resistor

The most commonly used is the 4 band resistor, and the same as the 3-ring the first two color ring still represents the first two resistance values, the third color ring represents the multiplier, the only difference is that the fourth color ring represents the tolerance value, against the above resistor color table are: brown for 1, red for 2, green for the multiplier x 100000, gold for the difference ± 5%, calculated as: 12x100000 = 1200kΩ ± 5%.

5 band resistor

The 5 band resistor will have one more resistance value than the 4-ring. I believe you already know how to correspond to the table above: brown is 1, black is 0, black is 0, red is the multiplier x 100, brown is the difference ±1%, calculated as: 100x100=1000Ω ±1%.

6 band resistor

6 band resistor compared to 5 band resistor is just one more ring to represent the temperature coefficient, let's see how to read: red is 2, purple is 7, yellow is 4, black is the multiplier x1, red is the difference ± 2%, black is the temperature coefficient of 250 ppm/°C, calculated as: 274x1 = 274Ω ± 2%, 250 ppm/°C. The color code of the resistor can be read from the color code of the resistor.
The above is the resistor color code reading steps, how, you have learned?

Common resistor color code questions

1. Why are resistors color coded?
Resistors are relatively small, the color will be easier to print than the number, and there is a standard set of charts against.
2. Why are high voltage resistors not metal colored?
High voltage resistors require higher voltage and heat resistance characteristics, which would be affected by metal colors, so they are not used.
3. Do all leaded resistors rated up to 1 watt have a colored ring pattern?
Not exactly.
4. What is a zero ohm resistor?
It is a special component with zero resistance, usually used as a jumper in circuit boards. Although it has "resistor" in its name, it is not really a resistor.
5. What is a "reliability" band?
It is an additional color ring on the resistor that indicates the quality and durability of the resistor. This color ring is for military use and is not common for commercial use.
6. What is the resistor color code for 1000 Ω resistors?
Brown, Black, Black, Gold.